class_docstr: Simple TicTacToe Env, starts the game randomly half of the time.
code: def play_random_move(self):
      # Select open spaces.
      open_spaces = get_open_spaces(self.board_state)
  
      if not open_spaces:
          return False
  
      # Choose a space and mark it.
      pos = self.np_random.choice(open_spaces)
      i, j = decode_pos(pos)
  
      self.board_state[i, j] = -1
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import gym
  from gym import spaces
  from gym.utils import seeding
  import numpy
  from tensor2tensor.data_generators import problem
  from tensor2tensor.layers import modalities
  from tensor2tensor.rl import gym_utils
label_desc: Use image node_id 3 for calling the TicTacToeEnv obj's underlying member method code with example usage: obj.play_random_move() and returns: False